20 protons
20 electrons ( as much elctrons as protons because there has to be same positive and negative to have a neutral atom)
And the number of neutrons depends of the mass number but in that case, I think that it's a Calcium atom (Ca) and so there are 20 netrons.
Answer:
ok but this number is for school another one number soon tell you
The percent composition of each element can be calculated as follows:
% composition = (mass of element / total mass) * 100
The total mass of the quarter is given to be 5.670 grams
Mass of Cu = 5.198 grams
Mass of Ni = 0.472 grams
Substitute in the above equation to get the mass percentage of each element as follows:
% of Cu = (5.198/5.670) * 100 = 91.675%
% of Ni = (0.472/5.670) * 100 = 8.325%
We need to know how many valence electrons are present in a given molecule in order to determine its Lewis dot structure.
<h3>
What is Lewis dot structure?</h3>
Lewis dot structure is defined as the visual representation of atoms' electrons using a diagram. It describe the bonds that exist between a molecule's lone pairs of electrons and its atoms.
A lone pair of electrons on the atom with the formal charge of 1- can typically be converted into a bonding pair that is shared with the atom that has the formal charge of 1+ in order to reduce the formal charges when they are present.
Thus, we need to know how many valence electrons are present in a given molecule in order to determine its Lewis dot structure.
To learn more about Lewis dot structure, refer to the link below:
brainly.com/question/20300458
#SPJ1